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typhoon1010 October 20, 2016 11:47

Transient Solution Problem
 
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I would like to ask question about transient solution.

The model which I work on reach steady state conditions after approxiamately 10800s. I added picture.

I analyzed as statedy state solution. But result is not same transient solution due to the time scale reach steady state is very large.

I will try to analyze as transient solution.

time step < (smallest mesh size/velocity)

time step < 0.0006s

For 10800s

Time step size 0.0005
Number of time step 21600000

This take long time. How can I solve this problem. Is there sımple way for this.

Can you advise me.

Thank you in advance

Best Regards

babanjaria October 21, 2016 01:00

Try to do steady state with density and chose implicit approach

typhoon1010 October 21, 2016 04:35

Thank you for your answer. Could you please explain a little more.

Workshop Technologies October 21, 2016 05:56

in implicit method, the solution progresses stably, hence possible to get the desired solution. Whatever may be the solution method, it is important to analyze with reference to the physics of the problem.

If you can send a brief writeup about you case, we can provide you the specific solution for your case. you can send text messages on:
http://workshopwale.com/ or can email at: adarsh@workshopwale.com

Quote:

Originally Posted by typhoon1010 (Post 622273)
I would like to ask question about transient solution.

The model which I work on reach steady state conditions after approxiamately 10800s. I added picture.

I analyzed as statedy state solution. But result is not same transient solution due to the time scale reach steady state is very large.

I will try to analyze as transient solution.

time step < (smallest mesh size/velocity)

time step < 0.0006s

For 10800s

Time step size 0.0005
Number of time step 21600000

This take long time. How can I solve this problem. Is there sımple way for this.

Can you advise me.

Thank you in advance

Best Regards


typhoon1010 October 22, 2016 04:04

Quote:

Originally Posted by Workshop Technologies (Post 622388)
in implicit method, the solution progresses stably, hence possible to get the desired solution. Whatever may be the solution method, it is important to analyze with reference to the physics of the problem.

If you can send a brief writeup about you case, we can provide you the specific solution for your case. you can send text messages on:
http://workshopwale.com/ or can email at: adarsh@workshopwale.com

Thank you for your answer. I will try.

Best Regards.

babanjaria October 22, 2016 06:33

Actually the thing is in implicit the number of equations to be solved is same as tge number of variable hence a constructive approach is made to all the equations but in explicit each variable have different equation easy to solve but explocit depends on time where as implicit is time independent

typhoon1010 October 22, 2016 10:16

Quote:

Originally Posted by babanjaria (Post 622514)
Actually the thing is in implicit the number of equations to be solved is same as tge number of variable hence a constructive approach is made to all the equations but in explicit each variable have different equation easy to solve but explocit depends on time where as implicit is time independent


Thank you for your answer. I will try. and share result.


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